The present invention relates generally to a tape recorder applicable to different type tape cassettes, and more particularly to an apparatus for detecting the configurations of tape cassettes inserted and mounted in the tape recorder so as to identify the kinds of magnetic tapes encased in the tape cassettes to perform the recording and reproducing operation of a signal in accordance with the kind of the tape of the inserted and mounted tape cassette.
Recently, in the sound equipment field, digital type tape recorders which digitally record and reproduce an audio signal onto/from a magnetic tape are being developed for the sound quality increasing purposes. A portion of the digital type tape recorder takes the so-called S-DAT system, and the S-DAT system is similar in structure to the widely used conventional analog type tape recorders. Taking advantage of this similarity, a compatible type tape recorder is proposed which can record and reproduce both the digital and analog signals. The conventional compatible type tape recorder is arranged to be suitable for a conventional analog type compact cassette and a digital type compact cassette. As illustrated in FIG. 8, the analog type compact cassette (which will be referred hereinafter to as ACC) 1 is equipped with a thicker portion 1a partially provided at the front side to form an opening which can accommodate a magnetic head, a pinch roller and other components of a tape recorder and further equipped with reel hub hole 1b. On the other hand, as illustrated in FIG. 9, the digital type compact cassette (which will be referred hereinafter to as DCC) 2 is equipped with a shutter 2a which covers the magnetic tape in the opening in non-use and which, in use, is movable along the tape-travelling direction or the reverse direction to expose the magnetic tape to accommodate the magnetic head, pinch roller and others of the tape recorder.
Because of mounting both the ACC 1 and DCC 2 in the same tape recorder, the ACC 1 and DCC 2 are arranged to be substantially equal in the entire configuration or dimension to each other, while the ACC 1 has, as shown in FIG. 8, projections 1c formed on both side surfaces and the DCC 2 has, as shown in FIG. 9, a recess 2e formed in a portion of the lower surface in addition to a gripping recess 2b formed in a portion of the upper surface and gripping recesses 2c, 2d formed in portions (corresponding in position to portions of the ACC 1 indicated by 1d in FIG. 8) of both the side surfaces. In response to the insertion of the DCC 2 in a direction (transverse direction) perpendicular to the longitudinal directions, the conventional compatible type tape recorder detects the presence of the aforementioned recess 2e, formed in the portion of the lower surface, by means of a detection switch provided at a cassette-insertion position of the tape recorder, thus deciding the insertion of the DCC 2 into the tape recorder.
However, for example, in the case of a car-use tape recorder in which the tape cassette is arranged to be inserted and discharged into and from the tape recorder along the longitudinal directions, because of the restriction on the structure for the detection of the recess 2e, difficulty is encountered to identify the kind of the tape cassette in practice.